Research Projects

Because of cost, environmental concern, and limited availability, there is a massive drive for the development of "zero-cobalt” cathode materials for LIB for the sustainability of future EVs production. There is a need for the replacement of currently used ternary layered oxides LiNi1-x-yMnxCoyO2 to cobalt-free binary layered LiNi1-xMnxO2 and Li1+yNi1-xMnxO2. In the binary layered oxide, the operating voltage and energy density increase with an increase in the Nickel or lithium content. The overall energy can be increased by using Li-metal as the anode instead of graphite. However, an increase in Nickel and Lithium content in the cathode and Lithium metal reduces the battery's thermal and cyclic stability. Increasing the energy density of lithium-ion batteries without compromising safety is of paramount importance. However, the batteries fabricated using high nickel content layered oxide and Li-metal can quickly overheat due to overcharging and rapid discharging. In addition, when the cells are exposed to environmental heating during the practical application, explosion accidents, and firing can occur due to the battery's associated thermal runaway. A thermoelectric device, based on the principle of the Seebeck effect, can convert this heat generated across the pouch cell into electrical energy. A flexible thermoelectric generator (TEG) printed on the pouch cell will simultaneously help to prevent the temperature overshoot of the cell by converting the heat into electricity. The generated output electricity by the flexible TEG can be used effectively to charge another pouch cell at a low C-rate. Hence, when the pack of lithium ion pouch cells is engineered along with flexible TEG in such a way that loss in the energy due to overheating of one set of cells will be used to charge another set of cells, the efficiency of the pack will increase. Therefore, this project proposes to fabricate a pack consisting of two sets of pouch cells. Flexible TEG coated on one set of pouch cells in the pack will convert the heat energy generated during the charging-discharging to charge another set of cells in the pack. With the center focus on developing safe, Cobalt free high energy lithium metal battery, the methodology of the project consists (i) Developing lithium ion pouch cells with Co-Free divalent layered oxide derivatives (ii) theoretically investigating on the temperature rise due to the heat generation during lithium intercalation/deintercalation in lithium Co-Free divalent layered oxide (iii) Development of flexible thermoelectric grid on polymer coated aluminum pouch cell case (iv) Integration of two sets of Li-metal pouch cells in a module, where the heat generated in the first set will be converted into electric energy using thermoelectric grids, that will be used to charge the second set of cells.